Duxbury Harbor Maintenance Dredging
|Client:||USACE New England Division|
|Project Date:||October, 2015 - March, 2016|
Maintenance dredging of portions of the Federal Navigation Channel in Duxbury Harbor was completed via a contract awarded to the Cashman/Burnham JV by the U.S. Army Corps of Engineers, New England District. The Duxbury Harbor Federal Navigation project consisted of an 8-foot deep, 100-foot wide and 1-mile long Entrance Channel, and an 8-foot deep, 21-acre Anchorage in the inner harbor. The harbor had not been dredged since 1997, and the accumulated sediment made parts of the harbor dangerously shallow.
- Both the anchorage and entrance channel portions of the project had a one-foot overdraft to 9 feet.
- Work consisted of maintenance dredging of ~200,000 cubic yards of predominantly silt-clay by mechanical dredge; ~180,000 cubic yards from the Anchorage, and ~45,000 cubic yards from the Entrance Channel.
- A closed bucket was used while dredging in silty material to minimize turbidity adjacent to the dredge.
- Dredged sediment was transported and placed at the Cape Cod Bay Disposal Site located ~20 nautical miles from Duxbury Harbor.
- Some dredging was limited to an environmental window between Sept. 1 and December 31, 2015; the project was completed by March 2016.